VintaSoftImageing is a great tool with wonderful performance, though I do have some suggestions for improvement to minimize user interaction and provide greater programmatic control.

Ability to select an area within an image programmatically.

Ability to zoom to existing selection (whether selected by user or in source code) programmatically.

Fire event on the image viewer control when a selection is made. This event should be triggered whether the selection was made by the user or in source code.
The parameter passed to this event would provide coordinates of the selection made as an alternative to querying the Rectangle property of the underlying zoom tool.

Ability to assign selected index of thumbnail control. Currently this property is read only.To illustrate the need, the ImageViewerDemo has different values for Focused and Hovered ThumbNailAppearance properties. Clicking on a thumbnail to select a page, then using the numeric UpDown control to change the page leaves the thumbnail control with 2 different thumbnails highlighted with potentially different appearances. It appears the only way to synchronize the 2 focus highlights is by clicking on a thumbnail.

Provide tool support for both mouse buttons. For example, it appears that panning can only be done via the left mouse button.

In relation to the DragDropSelection tool it would be very usefull to be able to :
1. Set the background color for DragAndDrop tool.
2. Copy the selection to the internal buffer of library and later insert it
to another image or
3. If the annotationviewer is used to create an annotation based on the DragDrop selection to be able to cut copy or paste elsewhere.
4. When croping part of an image to crop and display in a new page/image rather than just displaying the cropped part.
Regards

Sorting of images that looks alike in the ThumbnailsViewer/AnnotationThumbNailsViewer;
Batch stamping/Annotating of multiple-images, thumbnails of which having been selected in the ThumbnailsViewer;
Adding a tag property to each thumbnail which is also the tag of the image shown in the ImageViewer;
Built-in sortable/groupable grid of the annotations, each column being fetched from a CSV stored as text of the annotation.
Alfonso